Larsen received a bachelor's degree from UC Santa Barbara in 1990, a master's degree in theatre and film from BYU in 1993, and a PhD from Northern Illinois University in 2000.

In the summer of 2010, Larsen received Professional Development funds from the College of Fine Arts and Communications to help support his trip to Poland to deliver the keynote address at the Monty Python Conference held at the University of Lodz, Poland. The conference was organized by the academic Conference in Cultural Studies, sponsored by the Department of British Literature and Culture at the University of Lodz. Additionally, he was awarded the Alcuin Fellowship from BYU in 2006.

He has published two editions of Monty Python’s Flying Circus: An Utterly Complete, Thoroughly Unillustrated, Absolutely Unauthorized Guide to Possibly All the References From Arthur "Two Sheds" Jackson to Zambesi (Taylor Trade, 2013; Scarecrow, 2008), as well as Monty Python, Shakespeare and English Renaissance Drama (McFarland, 2003).

In 2015, A Book about the Film Monty Python and the Holy Grail: All the References from African Swallows to Zoot was published by Rowman & Littlefield.